A highly sensitive and responsive fluorescent probe based on 6-azide-chroman dye for detection and imaging of hydrogen sulfide in cells.

Hydrogen sulfide or H2 S is known as an important gasotransmitter involved in regulation of many physiological and pathological processes. Since a small amount of H2 S is produced by endogenous cells in the body and microorganisms in the gastrointestinal tract (GI tract), the current detection probes are limited for their use in measurement of unpretentious change of H2 S level both in vitro and in vivo. Therefore, development of a highly sensitive and responsive fluorescent probe for measurement of H2 S in vivo is of great significance for investigation of H2 S function and toxicity. Here, we designed a novel fluorescent probe AC-N3 through introducing azide in 6-position of chroman dye based on the hypothesis that 6-position (para-position) of chromone may be a potential trigger of fluorescent properties. The probe AC-N3 exhibits a better selectivity without interference from analytes, high sensitivity and little cytotoxicity. In addition, we confirmed that the conversion of electron-donating group in 6-position of chromone can trigger the change of fluorescence, which can be applied to design of other fluorescent probes.